has onyone added a turbo to a STOCK d21 with the z20e engine?? mines a 94 model. was thinking of running 6 or 7 PSI. the stock engine has like 78hp or something (terrible, i know). whats my best option, add a turbo to my z20e, or get a z24 (or possibly a turbo z24)? and what else is required to add a turbo at that much psi? (i know nothing about turbos, how they work and what is needed to add one)
cheers.

many people have turboed the Z20/22/24 engine. 7psi ain't much, stock motor will handle it as long as you give it enough fuel. Thats the most important thing. Can't do much with the stock efi system on that engine so a standalone engine management or adding an ekstra injector or two(simplest and cheapest solution) is your best option for more fuel.
You are gonna need an air/fuel gauge, turbo and turbo manifold, piping and perhaps an intercooler.
I recommend you read up on how all this works, if not you're not gonna understand how it all comes together and probably fail.
Howstuffworks.com is a good informational page, engineering explained is a good youtube channel with information on how turbos work.

What Spiff said. Unfortunately if you don't have the background knowledge or skills to do it yourself you may not be able to complete even a simple turbo upgrade.

You could possibly get away with running very low boost with a small turbo, but would depend on your driving style. Post a picture of your engine bay, would think there should be plenty of room to work with on a navara with a single cam engine.

Would a Z18et exhaust manifold fit? If yes, you could fit one, fit a turbo with a T3 flange (R33 RB25det turbo?), drill a hole in the sump and screw in a brass barb fitting for oil return. Put a T junction on your oil sender off the block and use it as an oil feed to the turbo, run pipe work to the throttle body, weld a dump pipe, chuck a filter on (yes I'm simplifying) and potentially go driving.

thanks guys. will post a pic some time tomorrow when i find some time to take one and upload it. i couldnt find much info on turboing a z20 so i thought id ask. what i will more than likely do is purchase all needed parts and then send it into my mechanic to hook it up (would do it myself, but mod plate and all that crap needs to be done apparently and i cant do that myself(that im aware of at least) as istill wasnt it to be street legal here in NSW for me as a P Plater.